Temporary power supplier Aggreko says trading has been better than expected during the last three months of the year, leaving 2009 operating profit up by more than a quarter.The company predicts operating profit of around £260m, about 27% higher than last year, while revenue should be 'slightly over £1bn', around 7% ahead of 2008.It added that revenue and profit in 2009, which will benefit from being a 53-week financial year, will be down 5% and up 4% respectively on a constant currency basis.It said the International Power Projects business has continued to trade strongly during the final quarter, with revenue for the fourth quarter at constant currency, excluding fuel and adjusted for the 53rd week, seen up 8%. "Looking ahead to next year, and allowing for the impact of the 53rd week in 2009, we expect that the group will make further progress on a constant currency basis," said the firm.It also looks forward to a strong year for major events, which should help the Local business division. Aggreko is the official supplier of power and temperature control for the Winter Olympics in Vancouver.Broker Ambrian keeps the shares as a 'buy' and ups its 2009 pre-tax profit forecast by £10m to £245m and 2010 forecasts by over £30m to £236.5m. 'Whilst the recent strong share price performance might prompt profit taking in the short term, the longer-term growth outlook for the group remains excellent,' it said.Final results are due on 4 March.